Pillow pack wrapping technique and related apparatus

CROSS REFERENCE TO RELATED APPLICATIONS

00002This application claims priority under 35 USC §119 from provisional application, U.S. Ser. No. 60/372,354, filed Apr. 10, 2002, the entire contents of which are herein incorporated by reference.

FIELD OF THE INVENTION

00003This invention relates to the field of packaging, and in particular to a method for hermetically wrapping bulk articles, such as confectionaries and pharmaceutical products, among others.

BACKGROUND OF THE INVENTION

00004Hermetic wraps, such as so-called “pillow” wraps, have been developed to more or less hermetically seal a wrapped bulk article such as candies, gum and the like. To date, these wraps have been performed on horizontal wrapping machines which require a significant footprint and are expensive to maintain and install.

00005Rotary cut and wrapping machines, on the other hand, which do not require as significant a footprint as the above horizontal wrapping machines have been used to package confections, chews, bubble gum and the like. These machines utilize sealing methods that have been limited to various die fold end wraps, twist wraps, turned under fold single point wraps and the like. To date, existing rotary wrapping machines have not been able to produce a “pillow type” hermetic seal or wrap at cost-effective speeds exceeding 500 pieces per minute.

SUMMARY OF THE INVENTION

00006It is a primary object of the present invention to overcome the above-noted deficiencies of the prior art.

00007It is another primary object of the present invention to develop a more efficient method for wrapping bulk articles, such as, for example, confectionaries and pharmaceutical products.

00008Therefore and according to one aspect of the invention there is disclosed a method of wrapping a bulk article, said method including the steps of: <ul id="ul100001" list-style="none"><li id="ul100002-li00002"><ul id="ul100002" list-style="none"><li id="ul100002-p00009" num="00009">placing a bulk article in wrapping material, said wrapping material being defined as a strip having ends extending over respective sides of said article and beyond the edges of the article, each of the extending ends of said strip having different lengths;</li><li id="ul100002-p00010" num="00010">folding each of said extending edges of said strip over one edge of the article, so as to define a fin-like section;</li><li id="ul100002-p00011" num="00011">heat sealing the fin-like section to define an axial seam wherein said fin-like section is sealed away from the wrapped article; and</li><li id="ul100002-p00012" num="00012">sealing the lateral ends of the wrapping strip so as to define a hermetic seal about the article.</li></ul></li></ul>

00013The article can include a variety of items, including but not limited to hard and soft chewy candies, gum, foodstuffs, and pharmaceutical (human and veterinary) products.

00014According to another aspect of the invention, there is described an apparatus for wrapping at least one bulk article, said apparatus including a rotary wheel having a plurality of pockets along an outer periphery thereof, said wheel being supported for rotation about a center axis of the wheel. A bulk article is fed into a first pocket of said wheel and into a strip of wrapping material. The strip of wrapping material is sized to be fitted about the periphery of the article and includes a pair of ends of dissimilar length extending from respective sides of the article. The article is then rotated to a second position by the pocket wheel which folds each of the ends of the wrapping material strip over an edge of the article and forms a fin-like section extending away from the article.

00015Preferably, a heater is provided adjacent to one of said pockets for heat sealing this fin-like section of wrapping material. This sealing operation does not require contact with the article being wrapped and therefore no heat or pressure is imparted to the article, but only to the fin-like section. In lieu of heat sealing, other sealing means, such as ultrasonic welding and/or pressure sensitive cold seals, can be utilized.

00016The formed seal is then cooled at a subsequent operation, such as by means of a water chiller or other appropriate apparatus. The article is then removed from the pocket wheel and the fin-like seal is folded over onto the top of the product which is then conveyed through an end seal apparatus to complete the hermetic seal operation.

00017An advantage of the above wrapping method is that a seal is created which extends away from the product permitting heat contact over substantially an entire major dimension (e.g., length, width) of the wrapped product.

00018These and other objects, features and advantages will be readily understood from the following Detailed Description which should be read in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

00019<figref idref="DRAWINGS">FIG. 1</figref> is a pictorial view of a wrapping method for a bulk article in accordance with a preferred embodiment of the invention;

00020<figref idref="DRAWINGS">FIGS. 2A and 2B</figref> are side elevational views of a wrapping apparatus used for carrying out the wrapping method of <figref idref="DRAWINGS">FIG. 1</figref>;

00021<figref idref="DRAWINGS">FIG. 3</figref> is an enlarged view of a pocket wheel station shown in <figref idref="DRAWINGS">FIG. 2A</figref>, illustrating the heat sealing of a fin section of the bulk article depicted in <figref idref="DRAWINGS">FIG. 1</figref>;

00022<figref idref="DRAWINGS">FIG. 4</figref> is an enlarged view of a pocket wheel station subsequent to that of <figref idref="DRAWINGS">FIG. 3</figref>, illustrating a cooling operation of the bulk article;

00023<figref idref="DRAWINGS">FIG. 5</figref> is an enlarged view of a subsequent pocket wheel station which provides an exit for the bulk article;

00024<figref idref="DRAWINGS">FIG. 6</figref> is a partial top view of the end sealing portion of the apparatus of <figref idref="DRAWINGS">FIGS. 2A and 2B</figref>; and

00025<figref idref="DRAWINGS">FIG. 7</figref> is a perspective view of a bulk article employing the wrapping method of FIG. <b>1</b>.

DETAILED DESCRIPTION

00026The following description relates to a specific apparatus for performing the present wrapping method. It will be readily apparent from the discussion that follows that other machinery can be used to create wrapped articles as described herein. The example shown herein relates to a rectangularly shaped bulk article, such as candy or gum but the herein defined wrapping method can easily be applied to articles of varying shapes and configurations.

00027Referring to <figref idref="DRAWINGS">FIG. 1</figref>, there is shown a pictorial view of the wrapping method in accordance with the present invention. A bulk article <b>10</b>, such as a continuous section of chocolate, caramel, or other confectionary or other material of example, such as fudge or dough, is first cut into a rectangular configuration from a feed line <b>20</b> through conventional means, such as a cutting blade (not shown). Referring to <figref idref="DRAWINGS">FIGS. 1 and 2A</figref>, the bulk article <b>10</b>, after being cutting into its rectilinear shape, is horizontally shuttled to a cut and wrap station, shown generally as <b>24</b>, adjacent a rotatable pocket wheel <b>28</b>. The cut and wrap station <b>24</b> is modified to allow a strip of wrapping material <b>32</b> to be fed from a supply of wrapping material (not shown) prior to the article <b>10</b> being pushed horizontally into a rotary folding box <b>36</b> of the pocket wheel <b>28</b>. The wrapping material <b>32</b> is composed of polyethylene, mylar, wax paper, foil or other suitable film material and typically includes a heat activated adhesive usually coated on the inside of the material which can include printed material on the outside surface thereof. The herein-described pocket wheel <b>28</b> includes a plurality of rotary folding boxes <b>36</b> disposed arcuately about the wheel, defining a number of take-up positions for bulk articles <b>10</b> as the wheel is caused to rotate through a central mechanism (not shown). As shown in <figref idref="DRAWINGS">FIG. 1</figref>, first and second folds <b>40</b>, <b>44</b> of the wrapping material strip <b>32</b> are created around the bulk article <b>10</b> along respective edges <b>48</b> and <b>52</b>.

00028The strip of wrapping material <b>32</b> that is provided is sized such that an additional amount of wrapping material remains outside of the rotary folding box <b>36</b> on each of the edges of the bulk article <b>10</b> to be wrapped, permitting this material to be folded back upon itself. Preferably, the material <b>32</b> is at least half the width of the product shape in a double thickness as required in a subsequent step.

00029Each rotary folding box <b>36</b> of the pocket wheel <b>28</b> of the herein described apparatus is preferably equipped with a pressure block <b>56</b> that is attached to the back of each pocket. This block <b>56</b> is made sufficiently wide, intentionally exceeding the desired width of the wrapping material and having a radial length sufficient to backup the overlap of material protruding from it when the bulk article <b>10</b> and the material are clamped together into contact.

00030As shown in <figref idref="DRAWINGS">FIGS. 1-4</figref>, the partially wrapped article <b>10</b> is then caused to index with the pocket wheel <b>28</b> within the folding box <b>36</b> and rotate through a series of consecutive stations of the apparatus. At first station approximately 90 degrees from the original wrap and cut station <b>24</b>, a heater <b>60</b> heaving a concave contact surface <b>64</b> is disposed in relation to the pocket wheel <b>28</b>, shown more particularly in FIG. <b>3</b>. The heater <b>60</b> includes a spring loaded mechanism <b>70</b> that acts to press onto and heat the overlapped material inside the pressure block <b>56</b> it rests upon. This allows the heat seal to occur away from the formed product and more specifically behind and away from the bulk article <b>10</b>. The heat seal forms a fin-like section <b>68</b>, shown more particularly in <figref idref="DRAWINGS">FIG. 1</figref>, which defines an axial seam as well as respective third and fourth folds <b>72</b>, <b>76</b>. In lieu of a heat seal, the seam can be formed using an ultrasonic horn (not shown) and a welding process.

00031After a given number of indexing operations, the bulk article <b>10</b> is pinched using a similar spring-loaded mechanism <b>82</b> similar to that described above relative to a water-chilled concave cooling station <b>80</b> having a similar contact surface <b>86</b>. This cooling operation sets the long axial adhesive of the seam of the defined fin section as shown in <figref idref="DRAWINGS">FIG. 4</figref>, as the wheel rotates past the contact surface <b>86</b> thereof.

00032The wrapped package then proceeds incrementally to an exit position or station <b>90</b>, shown in <figref idref="DRAWINGS">FIG. 5</figref>, from the rotating folding box <b>36</b> of the pocket wheel <b>28</b> and dwells horizontally. In this position as conveyed, the axial seam is now turned over 180 degrees from the sealed positions described above, and is “above” the product.

00033As the wrapped bulk article <b>10</b> is extracted from the rotary folding box of the pocket wheel <b>28</b>, the product is passed beneath a heel <b>84</b> of the concave surface of the cooling station <b>80</b>. Simultaneously, the long seam of the fin-like section <b>68</b> is pushed onto the top of the exiting product, thereby creating a final fold.

00034As the wrapped bulk article <b>10</b> emerges from under the heel <b>84</b> of the cooling block and exits the rotatable pocket wheel <b>28</b>, the article is placed within a chain lug style conveyor <b>88</b> disposed between a shallow track and a spring loaded hold-down bar <b>94</b>, which keeps the partially wrapped article <b>10</b> in place throughout a plurality of various end seal positions.

00035Once located within the chain lug conveyor <b>88</b>, the wrapped article <b>10</b> is pushed between a pair of package endformers <b>100</b>, situated on each lateral side thereof as shown in FIG. <b>6</b>. These endformers <b>100</b> are machined with respective lead-ins <b>104</b> that are used to capture the lateral ends of wrapping material <b>32</b> and to guide the ends which are closed between a set of narrow slots <b>108</b>. This operation, as shown in <figref idref="DRAWINGS">FIG. 6</figref>, flattens and spreads each end of the wrapping material <b>32</b> into a bow tie-like shape extending approximately halfway up the ends of the bulk article <b>10</b>.

00036After the lateral ends of the wrapped product have been flattened and shaped, each bulk article <b>10</b> is moved into an end heat portion <b>112</b> of the wrapping apparatus. In this portion, the ends of the wrapped bulk article <b>10</b> are moved through closely fitted slots <b>116</b> that have been machined into a pair of metal blocks <b>120</b>, <b>124</b>. These blocks <b>120</b>, <b>124</b> are heated, for example, by electrical resistance type heaters (not shown), that are controlled by self-monitoring heat controllers (not shown). The heater blocks <b>120</b>, <b>124</b> are preferably contained with temperature sensors in a conventional manner that report the achieved temperature to the control station through a feedback circuit which determines whether more or less heat is required. As the wrapped bulk article <b>10</b> passes through the slotted heated portions, the lateral ends of the wrapped bulk article <b>10</b> are subjected to a predetermined amount of heat over the length of the heater blocks <b>120</b>, <b>124</b>.

00037As a result of the above heating operation, the adhesive material on the interior of the ends of the wrapping material of the bulk article <b>10</b> is melted and gently pressed together and held in the above preformed bow tie shape. The heater blocks <b>120</b>, <b>124</b> are preferably mounted with fasteners through lateral slots that permit adjustment of the distance from the heaters to the actual product in the wrapping apparatus. Significant to the present invention, the above operation allows only the end wrapping material to be pressed against the heaters, and not the actual contained product.

00038After a predetermined amount of heater length, the end seal areas of the wrapped article <b>10</b> are resented between a pair of counter rotating end crimpers <b>130</b>, driven by the control system to a specific surface speed. These crimpers <b>130</b> provide the pressure required to set a firm seal with various style impressions being left on the ends. The long seam is tacked down at each end of the bulk article <b>10</b> by leaving a slight amount of length on the outer layer of exposed wrapping material, thereby completing the wrapping operation. For very poor heat conducting films and laminated wrapping materials, additional heaters may be applied to the crimpers.

00039Preferably, a reciprocating nip blade is provided in order to cut a small mark <b>140</b> or notch length wise into one end of the wrapped article <b>10</b> to permit easy opening by the consumer, such as shown in FIG. <b>7</b>.

00040While the present invention has been particularly shown and described with reference to the preferred mode as illustrated in the drawing, it will be understood by one skilled in the art that various changes in detail may be effected therein without departing from the spirit and scope of the invention as defined by the claims.

00041For example, the above equipment could also be utilized to wrap product having cold seal films. For this instance, the above described heater and chiller stations would simply be turned off and a label registration/cut/timing system (not shown) would be added to the cut and wrap station <b>24</b>.

PART LIST FOR FIGS.

1

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7

00002<tables id="TABLE-US-00001" num="00001"><table frame="none" colsep="0" rowsep="0"><tgroup align="left" colsep="0" rowsep="0" cols="2"><colspec colname="1" colwidth="98pt" align="char" /><colspec colname="2" colwidth="119pt" align="left" /><thead><row><entry namest="1" nameend="2" align="center" rowsep="1" /></row></thead><tbody valign="top"><row><entry>10</entry><entry>bulk article</entry></row><row><entry>20</entry><entry>feed line</entry></row><row><entry>24</entry><entry>cut and wrap station</entry></row><row><entry>28</entry><entry>rotatable pocket wheel</entry></row><row><entry>32</entry><entry>wrapping material</entry></row><row><entry>36</entry><entry>rotary folding box</entry></row><row><entry>40</entry><entry>first fold</entry></row><row><entry>44</entry><entry>second fold</entry></row><row><entry>48</entry><entry>edge</entry></row><row><entry>52</entry><entry>edge</entry></row><row><entry>56</entry><entry>pressure block</entry></row><row><entry>60</entry><entry>heater</entry></row><row><entry>64</entry><entry>concave contact surface</entry></row><row><entry>68</entry><entry>fin-like section</entry></row><row><entry>70</entry><entry>spring loaded mechanism</entry></row><row><entry>72</entry><entry>third fold</entry></row><row><entry>76</entry><entry>fourth fold</entry></row><row><entry>80</entry><entry>cooling station</entry></row><row><entry>82</entry><entry>spring loaded mechanism</entry></row><row><entry>84</entry><entry>heel</entry></row><row><entry>86</entry><entry>contact surface</entry></row><row><entry>88</entry><entry>conveyor</entry></row><row><entry>90</entry><entry>exit station</entry></row><row><entry>94</entry><entry>hold down bar</entry></row><row><entry>100</entry><entry>end formers</entry></row><row><entry>104</entry><entry>lead-ins</entry></row><row><entry>108</entry><entry>slots</entry></row><row><entry>112</entry><entry>end heat portion</entry></row><row><entry>116</entry><entry>slots</entry></row><row><entry>120</entry><entry>block</entry></row><row><entry>124</entry><entry>block</entry></row><row><entry>130</entry><entry>crimper</entry></row><row><entry>140</entry><entry>slot/notch</entry></row><row><entry namest="1" nameend="2" align="center" rowsep="1" /></row></tbody></tgroup></table></tables>

00042It will be readily apparent to one of sufficient skill in the field that certain modifications and variations covering the inventive concepts are possible as recited in the following claims: